The present invention relates to a coupling of the ball-and-socket joint type between two objects, comprising coupling members connected to each object. The one object may consist, for example, of a work table, a tool, weapon or instrument holder etc. while the other object may consist for example, of a stand, a foot or a base etc. for example for one of the first-named objects.
A particularly advantageous field of application for the coupling according to the invention is for driver's seats in working vehicles such as forestry machines, agricultural machines, earth movers, excavators etc. The technical development of this type of vehicles has been very rapid. The same applies to the development on the military side for example of tanks. The development of driver ergonomics has not kept pace, however. In certain cases--despite the fact that the driver's technical aids have certainly been improved--it may even be maintained that driver ergonomics have become worse since the stresses have increased in keeping with the better traversability of the terrain, the higher speeds etc. There are therefore great deficiencies still both in older and in newly constructed machines with regard to driver's seats inter alia, and the cases of sickness directly related to faulty ergonomics are common. In order to avoid various form of fatigue through faulty positions of the body, therefore, the driver's working milieu must be radically renewed and an ergonomically logical development of the seat must take place. Particularly noteworthy is the need of for devices for making the driver's seat horizontal in working vehicles in forestry and agriculture, in mines and other work places. In forestry one can point out, inter alia, how extremely tiring it is to work for long shifts in a machine which is standing on inclined ground without any possibility of making the work seat horizontal. In agriculture, ploughing work involves heavy stresses on the back as a result of the fact that the machine is inclined the whole time. The need for couplings by means of which the driver's seat can be made horizontal or otherwise be adjusted in relation to a base is therefore very great.